[PATCH 0/3] fio: fix eta

[Keith Busch <kbusch@meta.com>]

From: Keith Busch <kbusch@kernel.org>

When jobs are overlapping or serialized by the stonewall, the eta
calculation messes up by restarting back to the original calculated
time. Here's a simple example of running multiple 5 second jobs with the
stonewall to serialize them:

  $ fio --eta-newline=1 --name=global --ioengine=io_uring --rw=randread \
      --filename=/dev/zero --time_based --runtime=5 --size=10T --stonewall \
      --name=a --name=b --name=c --name=d --name=e
  ...
  Jobs: 1 (f=1): [r(1),P(4)][15.4%][r=837MiB/s][r=214k IOPS][eta 00m:22s]
  Jobs: 1 (f=1): [r(1),P(4)][19.2%][r=737MiB/s][r=189k IOPS][eta 00m:21s]
  Jobs: 1 (f=1): [_(1),r(1),P(3)][25.0%][r=1569MiB/s][r=402k IOPS][eta 00m:24s]
  Jobs: 1 (f=1): [_(1),r(1),P(3)][31.2%][r=2045MiB/s][r=523k IOPS][eta 00m:22s]
  Jobs: 1 (f=1): [_(1),r(1),P(3)][37.5%][r=1722MiB/s][r=441k IOPS][eta 00m:20s]
  Jobs: 1 (f=1): [_(2),r(1),P(2)][35.1%][r=374MiB/s][r=95.6k IOPS][eta 00m:24s]
  Jobs: 1 (f=1): [_(2),r(1),P(2)][40.5%][r=2193MiB/s][r=561k IOPS][eta 00m:22s]

Literally unplayable! ;)

This series gets the eta reporting the correct value.

Keith Busch (3):
  eta: don't estimate runtime from an unset job epoch
  eta: cap the ETA at the job's own remaining runtime
  eta: remove now unused done_secs

 backend.c |  2 --
 eta.c     | 39 +++++++++++++++++++++++++++++----------
 fio.h     |  1 -
 libfio.c  |  1 -
 4 files changed, 29 insertions(+), 14 deletions(-)

-- 
2.52.0